Finger at offer34 — the first character position that appears only once

Topic describes

Find the first character that occurs only once in a string (0<= string length <=10000, all letters) and return its position, or -1 (case sensitive) if none exists.

Answer key

#include <iostream>
#include <string>
#include <map>

using namespace std;

int FirstNotRepeatingChar(string str)
{
	map<char.int> m;
	for (int i = 0; i < str.length(a); i++) m[str[i]]++;for (int i = 0; i < str.length(a); i++) {if (m[str[i]] == 1)
			return i;
	}
	return - 1;
}

int main(a)
{
	ios::sync_with_stdio(false);
	string s;
	cin >> s;
	cout << FirstNotRepeatingChar(s) << endl;
	return 0;
}
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